How are local plant disease symptoms different from systemic symptoms?

In the study of plant disease, symptoms are categorized based on the extent of the host tissue affected.1

• Local symptoms refer to physiological or structural changes that occur within a limited, specific area of the host tissue. Examples of these localized expressions include leaf spots, galls, and cankers.1
• Systemic symptoms involve the reaction of a much larger portion of the plant or the entire organism. These symptoms often reflect the broader physiological impact of a disease, such as wilting, yellowing, or dwarfing.1

While local symptoms are the direct result of pathogen activity in a specific location, systemic symptoms can also be secondary, resulting from the physiological effects of a disease on distant tissues or uninvaded organs. For instance, while a root infection may be localized, the resulting wilting of the leaves is a systemic symptom caused by the plant's inability to transport water effectively.12